PVALB

Fig1. The interplay of cell types and pathways in sporadic ALS (SALS) pathology.

What is PVALB protein?

PVALB (parvalbumin) gene is a protein coding gene which situated on the long arm of chromosome 22 at locus 22q12. Parvalbumin alpha, also known PVALB, belongs to a larger group of EF hand proteins. It is a high affinity calcium ion-binding protein that is structurally and functionally similar to calmodulin and troponin C. Parvalbumin is expressed in a specific population of GABAergic interneurones which are thought to play a role in maintaining the balance between excitation and inhibition in the cortex as well as the hippocampus. The PVALB protein is consisted of 110 amino acids and its molecular mass is approximately 12.1 kDa.

What is the function of PVALB protein?

PVALB is a small molecule calcium-binding protein that is mainly found in neurons of the central nervous system and plays a key role in the function and regulation of neurons. PVALB regulates neuronal excitability by binding and regulating the concentration of free calcium ions in cells. When PVALB binds to calcium ions, neuronal excitability decreases. When PVALB releases calcium ions, neuronal excitability increases. PVALB interacts with some sodium ion channels, making it also important in synaptic plasticity.

PVALB Related Signaling Pathway

PVALB protein binds to calcium ion with high affinity and can participate in signal transduction, muscle contraction and apoptosis. It can also influence transmitter release in presynaptic membrane and ion channel activity in postsynaptic membrane, thereby regulating the efficiency and pattern of synaptic transmission. It releases GABA in presynaptic neurons to inhibit neuronal excitability and is involved in regulating the synchrony and rhythm of neuronal networks.

PVALB Related Diseases

The abnormal expression of PVALB protein is closely related to the occurrence and development of neurological diseases such as epilepsy, Parkinson's disease and schizophrenia. In addition, abnormal PVALB function may be associated with brain injury, psychiatric disorders such as anxiety and depression.

Bioapplications of PVALB

Because PVALB plays an important role in a variety of diseases, it is also seen as a potential drug target. Researchers are exploring small molecule inhibitors or agonists that target PVALB to treat diseases such as Alzheimer's disease and epilepsy. PVALB is also used in the field of biotechnology, such as for the production of recombinant proteins, the development of new biological materials, and so on.

Case study 1: Janine Wörthmüller, 2018

Calretinin (CR; CALB2) belonging to the family of EF-hand Ca2+-binding proteins (CaBP) is widely used as a positive marker for the identification of human malignant mesothelioma (MM). No studies have yet investigated whether other closely related CaBPs might serve as substitutes for CR's functions(s) in MM cells.

Genetically modified MM cell lines with medium (MSTO-211H and ZL5) or low (SPC111) endogenous CR expression levels were generated that overexpress either CR's closest homologue calbindin-D28k (CB) or parvalbumin (PV). After lentiviral shCALB2-mediated CR downregulation, in both MSTO-211H and ZL5 cells expressing CB or PV, the CR deficiency-mediated increase in cell death was not prevented by CB or PV. In conclusion, CR has a likely unique role in MM that cannot be substituted by "similar" CaBPs.

Fig1. Protein expression levels of CR, calbindin-D28k (CB), and parvalbumin (PV) in SPC111 clones obtained by serial dilution by Western blot analyses.

Fig2. Estimated intracellular concentrations in SPC111 CaBP-overexpressing clones.

Case study 2: Valentina Medici, 2016

A consistent decrease in the number of inhibitory interneuronal subpopulation that expresses parvalbumin (PV) was reported in postsurgical tissue from patients with focal cortical dysplasia (FCD). The team tested if the decrease in PV protein expression observed in epileptic tissue corresponds to a parallel impairment in the γ-aminobutyric acid (GABA)ergic compartment.
Serial sections were processed using in situ hybridization with GAD-65 and GAD-67 probes and immunocytochemistry with antibody against PV. The density of inhibitory PV-immunoreactive interneurons in relation to GABAergic cells was estimated in controls. Field fraction and line profile analyses were added to estimate immunostaining proportion and distribution of PV signal generated in gray matter.

A reduction of PV-positive cells and PV-immunoreactivity was observed exclusively in FCD type I/III specimens compared with cryptogenic tissue from control patients with a poor postsurgical outcome. In FCD type II, a profound rearrangement in the cortical distribution of PV immunoreactivity was observed, without a quantitative reduction of the number of neurons and terminals.

Fig3. Methodologic aspects of 2D (A–B) analyses of PV-positive and GAD65/67-positive neuronal density.

Fig4. Confocal double immunofluorescence images combining in situ hybridization for GAD65/67 riboprobes with PV or SMI311 immunoreactivity.

PVALB has several biochemical functions, for example, calcium ion binding,protein heterodimerization activity,protein homodimerization activity. Some of the functions are cooperated with other proteins, some of the functions could acted by PVALB itself. We selected most functions PVALB had, and list some proteins which have the same functions with PVALB. You can find most of the proteins on our site.

PVALB has direct interactions with proteins and molecules. Those interactions were detected by several methods such as yeast two hybrid, co-IP, pull-down and so on. We selected proteins and molecules interacted with PVALB here. Most of them are supplied by our site. Hope this information will be useful for your research of PVALB.